See for example "Edith's" point in the linked article "Edith: There’s a difference between “let’s have a discussion” and “let me tell you what’s up, all you wrong people.”"

To me, it's really hard not to imagine the author being the type of person who would have a "I'm an Atheist, debate me" shirt. It's written in that style.

Beyond that I don't really know what to say. Technical discussions unfortunately frequently end up this way too, so maybe its easy to get used to it. But its counter-productive.

And note, I'm suggesting why it pissed people off at google and should have got him fired. It isn't an explanation of the media reaction per-say because in the context of a public discussion there is no precept that you are cooperating with people (unlike your co-workers) and your audience isn't going to repeatedly interact with you. So adversarial arguments are common and generally accepted. It would have been fine as an op-ed in a news paper (though IMHO doesn't make the quality bar). Its not in a discussion with co workers.

If we're going with anecdote, the memo sure read as a hostile dropped-bombshell to every female Googler I've talked to on the subject.

Regardless of whether it was the author's intent to do harm, or to be antagonistic, he absolutely did - both to individuals and the company as a whole.